Mezzmo icon not showing on TV.

Hi, today I have lost the mezzmo icon in the source options on my Samsung TV. It is normally there but now it's gone. Yes I have restarted mezzmo, my laptop and the TV several times in various orders but still not showing. I have a fetch box also and mezzmo is not showing there either. I have checked the internet connection on all devices and all show connection.
Any ideas?
Rob.

You will need to make sure that the laptop is in the same subnet on the local network as the TV. Check the ip address of the TV and also check the ip address of the laptop and compare the first three numbers. E.g. 192.168.0.x. If the first three numbers are different then multicast messages to/from the server will not be received by the TV.